"dry" orgasm?

Guys, have you ever experienced an orgasm but with no ejaculation? I was giving my fiance oral, and he orgasmed--everything about his body and reactions were normal, and he even said he orgasmed--but no fluid came out. We both thought it was strange. He'd never experienced it before. Is this normal? Something any of you guys have experienced before? Also, taking into consideration it was about the 5th time in 24 hours that he came? Just wondering, don't want to hurt the guy by doing it too much lol
Thanks!

I assume he was drained. Some men can't even reach orgasm without there being enough to ejaculate, so I would count him in the lucky category. But, yes, many men can orgasm without ejaculating and some men can orgasm without an erection.